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Vacuum - Reclaiming Unused Space In Odb

I was curious if you could assist me with a challenge we are having with our objectdb database.  Our odb files are about 50Gb in size and are written to about a million times a day with both adds and updates.  This is creating a lot of unused space in the database that we are wanting to reclaim.  Other database vendors provide a vacuum process to allow dumping a database to a flat file (basically a sql dump) and reload.  Is there a capability in ObjectDb to provide a vacuum?  The online backup feature appears to copy the dead space as well so isn't performing #1 2016-03-02 06:42 I was curious if you could assist me with a challenge we are having with our objectdb database.  Our odb fil ...

 
forum_thread

Efficient query on EmbeddedId

Hi! I have an entity class with an @EmbeddedId (field1 int and field2 int). Based on the manual, I understand that making a query just on entity.id.field1 is efficient. Of course, making a query containing the whole EmbeddedId is the ideal case, and I use it, but I need more use cases. #1 2014-07-25 16:29 Hi! I have an entity class with an @EmbeddedId (field1 int and field2 int). Based on the manual, I unders ...

 
api-jdo

javax.jdo.FetchGroup

FetchGroup represents a named fetch group for a specific class or interface.(Interface of JDO)

 
forum_thread

Eclipse/JPA database tutorial

Hello Sir/Madam, I followed all the steps correctly as given in the tutorial. But when i run it , I'm getting an error saying, the resource not available. Please help regarding the issue as soon as possible. Thank you. ... Maybe you ran the JSP as your main page rather than the servlet? In this example the servlet sets the ...

 
forum_thread

RT Java application recording into 100DB run OOM after a few hours.

Hi, I am running a java application that records data from 100 feeds into 100 different database - this is done is one thread. It works fine several hours - and suddenly i got an out of memory issue (I checked there is no leak in java - I cleared the entity manager every 10 new entity). 1/ I use the default objectDb.conf (i mean i dont use any - so it must be using the default somewhere). 2/ Using Netbeans, I profiled the application and I noticed that there is one thread (ODB FileWriter) running for each open DB. #1 2015-01-02 20:11 Hi, I am running a java application that records data from 100 feeds into 100 different database - this i ...

 
forum_thread

Connection is closed Caused by: java.io.EOFException

I am getting this exception on a regular basis, after a period of time of repeating the same code execution.  I don't understand why.  I restart the DB server and my code works again for another period of time until same exception is encountered again.  I cannot pin down a pattern e.g. after a certain period of time,  because the time  periods between exceptions are not regular, although frequent.  Any test case  I use will pass most of the time but will fail after an undetermined period. ... initial = "256kb" resize = "256kb" page = "2kb" /> <recovery enabled = "true" sync = ...

 
forum_thread

Degrading performance overtime

hi, We have an application that uses embedded odb database. We have configured odb to start at 50meg chunks and grow at 50 megs a time. as the files become larger between 1 and 2 gigs we start to see considerable degrade in performance caused internal objectdb locking: ... initial = "51200kb" resize = "51200kb" page = "2kb" /> <recovery enabled = "true" sync = ...

 
tutorial

Step 6: Set the Spring XML

Explains how to set XML in an Eclipse Spring MVC JPA web application project. To integrate the Spring Framework into a web application we have to add the definition of the Spring dispatcher servlet to the  web.xml configuration file and to configure that servlet using another xml configuration file. Open the  web.xml ...

 
forum_thread

multi thread application, id field sporadically null

We are testing objectDB with a multi thread application. Each thread has it's own entityManager created from a common factory. In one thread we receive sometimes an object from the database with the field that is declared as @Id having the value null (what is not correct, we checked that with the explorer). The class is declared like this: ... ... Good. See also this manual page, regarding setting a flush mode . ObjectDB ...

 
forum_thread

How to track memory leak with ObjectDb.

Hello, I suspect some memory leak in my application. ( turning app into OOM very fast ) In fact, some com.objectdb.o.MST objects are retaining a huge % of my heap space. While watching the dump file ( with Eclipse MAT ), i was not able to inspect carrefully the memory leak issue. That's is very hard to debug because of obfuscated objectdb code. Well, objectdb is closed source, ok so ... but, in production case, how can a developper do his debug job correctly with your obfuscated code ? ... 22:31 This shows the page cache. Its size in your example is not far from the default maximum ...